Behavioural evidence for self-medication in bumblebees?

The presence of antimicrobial secondary metabolites in nectar suggests that pollinators, which are threatened globally by emergent disease, may benefit from the consumption of nectars rich in these metabolites. We tested whether nicotine, a nectar secondary metabolite common in Solanaceae and Tilia species, is used by parasitized bumblebees as a source of self-medication , using a series of toxicological, microbiological and behavioural experiments. Caged bees infected with Crithidia bombi had a slight preference for sucrose solution laced with the alkaloid and behavioural tests showed that the parasite infection induced an increased consumption of nicotine during foraging activity, though nicotine had an appetite-reducing effect overall. When ingested, nicotine delayed the progression of a gut infection in bumblebees by a few days, but dietary nicotine did not clear the infection, and after 10 days the parasite load approached that of control bees. Moreover, when pathogens were exposed to the alkaloid prior to host ingestion, the protozoan's viability was not directly affected, suggesting that anti-parasite effects were relatively weak. Nicotine consumption in a single dose did not impose any cost even in starved bees but the alkaloid had detrimental effects on healthy bees if consistently consumed for weeks. These toxic effects disappeared in infected bees, suggesting that detoxification costs might have been counterbalanced by the advantages in slowing the progression of the infection. Nicotine consumption did not affect bee lifespan but the reduction in the parasite load may have other likely unexplored subtle benefits both for individual bees and their colony.  Potential evidence for self-medication is discussed. The contention that secondary metabolites in nectar may be under selection from pollinators, or used by plants to enhance their own reproductive success, remains to be confirmed.D.B. was supported by a Marie Curie Intra European Fellowship within the 7th European Community Framework Programm

Intraspecific variation in invertebrate cognition: a review

A well-established field of research in vertebrates focuses on the variability of cognitive abilities within species. From mammals to fish, numerous studies have revealed remarkable differences in the cognitive phenotype among individuals, particularly in terms of sex or personality. However, many aspects of the mechanisms, genetics, and selective pressures that underlie individual cognitive variation remain unclear. Surprisingly, intraspecific variability in cognition has received much less attention in invertebrates, despite the increasing evidence of remarkable cognitive abilities in this group and the insights that could be gained from examining simultaneously two distinct taxa, namely vertebrates and invertebrates. In this review, we provide evidence that certain invertebrate species exhibit all the key features of cognitive variation observed in vertebrates, including differences related to sex and personality. In many cases, invertebrate studies have provided insights into the genetic basis, evolvability and response to selection of cognitive variability. Moreover, we highlight evidence for caste differences in eusocial insects, which are linked to task specialisation within the colony. This makes insect eusociality a valuable system for understanding how selection influences cognitive variation. We propose that cognitive variation in invertebrates may be more widespread than currently thought, and that selection may operate in a similar manner on two distantly related cognitive systems (vertebrates and invertebrates). Finally, we suggest that invertebrates hold the potential to serve both as alternative and complementary models to vertebrates, contributing to a deeper understanding of cognitive evolution

La subfornitura meccanica in Emilia-Romagna fra crisi e riorganizzazione delle filiere. Quali strategie per competere

La ricerca presentata in questo rapporto è stata realizzata nell’ambito del progetto pro-mozionale, di cui all’art. 13 della Legge Regionale 09/02/2010 n. 1 Norme per la tutela, la promozione, lo sviluppo e la valorizzazione dell’artigianato, approvato con determina della Giunta Regionale Emilia-Romagna n. 2581 del 22/02/2016 dal titolo “Tra creativi-tà e tradizione: una nuova immagine dell’impresa artigiana nella subfornitura meccani-ca”. La finalità principale della ricerca riguarda l’analisi degli effetti della crisi e dei processi di riorganizzazione in atto nelle principali filiere dell’industria meccanica regionale sul-le caratteristiche e le prospettive delle imprese di subfornitura. Gli obiettivi conoscitivi sono, in particolare, l’analisi dei cambiamenti di tipo strutturale delle imprese, legati ai processi di internazionalizzazione dei mercati di sbocco e di ap-provvigionamento; l’analisi delle strategie seguite dalle imprese in risposta alla crisi e al nuovo contesto competitivo; l’analisi dell’evoluzione delle relazioni fra committenti e subfornitori